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      <title>如何在Nginx中实现基于用户认证的访问控制？ - 交互式测验</title>
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      </style>
    </head>
    <body>
      <div class="main-wrapper">
          <div class="quiz-container">
            <div class="quiz-header">
              <h1>如何在Nginx中实现基于用户认证的访问控制？ - 交互式测验</h1>
              <p>检验你对文档内容的理解程度</p>
            </div>
            <div id="quiz-content">
                <div class="quiz-body">
                    <div class="progress-bar">
                        <div id="progress-indicator"></div>
                    </div>
                    <div id="question-container">
                      <p id="question-text"></p>
                      <ul class="options-list" id="options-list"></ul>
                    </div>
                    <div id="result-container"></div>
                    <div id="hint-container" class="hint-container"></div>
                </div>
                <div class="quiz-footer" id="quiz-footer">
                  <button id="prev-btn" class="nav-btn">上一题</button>
                  <button id="hint-btn" class="nav-btn" style="background-color: #ffc107; color: #333; box-shadow: 0 4px 12px rgba(255,193,7,0.3);">提示</button>
                  <button id="next-btn" class="nav-btn">下一题</button>
                </div>
            </div>
          </div>
      </div>

      <script>
        const quizData = [
  {
    "question": "在使用 `htpasswd` 工具为 Nginx 创建密码文件时，命令 `htpasswd -c /etc/nginx/.htpasswd myuser` 中的 `-c` 选项表示什么？",
    "options": [
      "为用户指定一个自定义的加密算法 (Custom encryption)。",
      "检查 (Check) 密码文件是否存在且语法正确。",
      "创建一个新的密码文件。如果该文件已存在，原文件内容将被覆盖。",
      "向一个已存在的密码文件中追加 (Concatenate) 一个新用户。"
    ],
    "correctAnswerIndex": 2,
    "explanation": "根据文档描述，`-c` 选项专门用于创建（create）一个新的密码文件。这是一个关键且具有潜在风险的操作，因为如果文件已存在，它会被新的空文件覆盖。当需要向现有文件添加用户时，应省略 `-c` 选项。",
    "source": "文档中「1.1 创建密码文件」部分",
    "hint": "文档中提到：“-c 选项用于创建新文件。如果文件已经存在，省略 -c 选项来添加新用户。”"
  },
  {
    "question": "在 Nginx 配置文件中，要为一个 location 启用最基本的 HTTP 用户名/密码认证，必须配置的两个核心指令是？",
    "options": [
      "auth_basic 和 auth_basic_user_file",
      "allow 和 deny",
      "proxy_pass 和 proxy_set_header",
      "ssl_certificate 和 ssl_certificate_key"
    ],
    "correctAnswerIndex": 0,
    "explanation": "文档明确指出，`auth_basic` 用于设置认证区域的提示信息（会显示在浏览器的弹窗中），而 `auth_basic_user_file` 则用于指定包含用户名和加密密码的文件路径。这两个指令是实现 HTTP 基本认证的基础。",
    "source": "文档中「1.2 配置 Nginx 进行基本认证」部分",
    "hint": "想一想，你需要哪两个指令来分别设置认证提示和指定密码文件的位置？"
  },
  {
    "question": "根据文档，当需要使用标准版 Nginx 实现如 OAuth2 或 JWT 这类更复杂的认证时，通常采用哪种方法？",
    "options": [
      "Nginx 标准版内置了完整的 JWT 和 OAuth2 验证模块，直接启用即可。",
      "利用 `nginx-auth-request` 模块，将认证请求转发给一个外部的、独立的认证服务进行处理。",
      "必须购买商业版的 Nginx Plus，因为标准版完全无法处理这类认证。",
      "通过 `allow` 和 `deny` 指令，根据 Token 中的信息动态配置IP白名单。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "文档指出，Nginx 本身不直接支持 OAuth 或 JWT。正确的做法是使用 `nginx-auth-request` 模块，它允许 Nginx 在处理实际请求前，先向一个指定的后端认证服务发送一个子请求。由该服务来验证 Token 或凭证的有效性，然后根据其返回的 HTTP 状态码（2xx 或 4xx）来决定是放行还是拒绝原始请求。",
    "source": "文档中「2.1 使用 Nginx 认证模块」部分",
    "hint": "文档提到：“Nginx 本身不直接支持 OAuth 或 JWT，但可以通过第三方模块或与认证代理...集成来实现。”"
  },
  {
    "question": "在配置 `nginx-auth-request` 模块时，`auth_request /auth;` 这行指令的真正作用是什么？",
    "options": [
      "它定义了当认证失败时，用户将被重定向到的错误页面。",
      "它指定了一个内部 location (即 /auth)，Nginx 会向该 location 发起一个认证子请求。",
      "它将所有访问请求的日志都记录到名为 `/auth` 的文件中。",
      "它直接将客户端请求代理到名为 `/auth` 的后端服务。"
    ],
    "correctAnswerIndex": 1,
    "explanation": "`auth_request` 指令是 `nginx-auth-request` 模块的核心。它并不会直接代理用户请求，而是发起一个独立的、内部的子请求到它所指定的 location (`/auth`)。这个 location 内部再通过 `proxy_pass` 将认证任务委托给后端的认证服务器。",
    "source": "文档中「2.1 使用 Nginx 认证模块」部分",
    "hint": "该指令的解释是：“指定一个位置用于处理认证请求。”"
  },
  {
    "question": "如果你希望实现一个IP白名单策略：只允许来自 `192.168.1.0/24` 网段的访问，同时明确拒绝所有其他来源的IP，以下哪个配置是正确的？",
    "options": [
      "deny all; allow 192.168.1.0/24;",
      "allow 192.168.1.0/24; deny all;",
      "only_from 192.168.1.0/24;",
      "allow 192.168.1.0/24;"
    ],
    "correctAnswerIndex": 1,
    "explanation": "Nginx 的访问控制规则是按顺序匹配的。`allow 192.168.1.0/24;` 会首先检查请求IP是否匹配该网段，如果匹配，则允许访问并停止后续检查。如果第一个规则不匹配，则会继续检查下一条规则 `deny all;`，这条规则会匹配所有IP，从而实现拒绝访问。如果顺序颠倒，`deny all` 会首先匹配并拒绝所有请求。",
    "source": "文档中「3. 配置 IP 白名单和黑名单」部分",
    "hint": "Nginx 会按顺序检查访问控制指令。思考一下，应该先允许特定的，再拒绝其余的，还是反过来？"
  },
  {
    "question": "文档在“配置和优化”章节中特别强调，为了保障认证过程的安全性，强烈建议与哪项技术结合使用？",
    "options": [
      "HTTP/2 协议以加速认证过程。",
      "配置负载均衡以分担认证压力。",
      "定期更新 Nginx 版本。",
      "配置 HTTPS (SSL/TLS) 来加密传输中的敏感数据。"
    ],
    "correctAnswerIndex": 3,
    "explanation": "HTTP 基本认证传输的用户名和密码仅经过 Base64 编码，并非加密，很容易在网络传输中被窃听和破解。因此，文档强烈建议启用 HTTPS，通过 SSL/TLS 对整个通信链路进行加密，从而保护认证凭证和其他敏感数据不被泄露。",
    "source": "文档中「4.1 配置 HTTPS」部分",
    "hint": "当用户名和密码在网络上传输时，最需要担心的是什么问题？如何从根本上解决这个问题？"
  }
];
        console.log("Quiz Data:", JSON.parse(JSON.stringify(quizData))); // 添加这行用于调试，以可展开的JSON格式输出
        
        let currentQuestionIndex = 0;
        let score = 0;
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        const optionsListEl = document.getElementById('options-list');
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        const quizContentEl = document.getElementById('quiz-content');
        const progressIndicatorEl = document.getElementById('progress-indicator');
        const prevBtn = document.getElementById('prev-btn');
        const nextBtn = document.getElementById('next-btn');
        const hintBtn = document.getElementById('hint-btn');
        const hintContainerEl = document.getElementById('hint-container');

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          optionsListEl.innerHTML = '';
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            return;
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            li.textContent = optionText;
            li.dataset.index = index; // Store index in a data attribute
            // 如果这道题已经回答过，恢复状态
            if (userAnswers[currentQuestionIndex] !== null) {
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                    li.classList.add('selected');
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            optionsListEl.appendChild(li);
          });

          // 如果已经回答过，直接显示结果
          if (userAnswers[currentQuestionIndex] !== null) {
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          updateNavigationButtons();
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        function selectOption(optionIndex) {
            userAnswers[currentQuestionIndex] = optionIndex;
            const currentQuestion = quizData[currentQuestionIndex];
            const isCorrect = optionIndex === currentQuestion.correctAnswerIndex;

            // 重新计算分数
            score = userAnswers.reduce((acc, answer, index) => {
                return answer === quizData[index].correctAnswerIndex ? acc + 1 : acc;
            }, 0);

            showResult(isCorrect, currentQuestion);
            updateNavigationButtons();
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            prevBtn.style.display = 'block';
            nextBtn.style.display = 'block';
            hintBtn.style.display = 'block'; // 显示提示按钮

            prevBtn.disabled = currentQuestionIndex === 0;
            nextBtn.disabled = false; // 最后一题时，下一题按钮不禁用，而是用于显示报告
            nextBtn.textContent = (currentQuestionIndex === quizData.length - 1) ? '查看报告' : '下一题';
            
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                hintBtn.disabled = true;
                hintContainerEl.style.display = 'none';
                hintContainerEl.textContent = ''; // 清除旧的提示内容
            } else {
                hintBtn.disabled = false;
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        function showResult(isCorrect, questionData) {
            resultContainerEl.innerHTML = ''; // 清空之前的结果
            const resultBox = document.createElement('div');
            resultBox.className = `result-box ${isCorrect ? 'correct' : 'incorrect'}`;
            
            let html = `<h3>${isCorrect ? '回答正确！' : '回答错误'}</h3>`;
            if (!isCorrect) {
                html += `<p><strong>正确答案是：</strong> ${questionData.options[questionData.correctAnswerIndex]}</p>`;
            }
            html += `<div class="explanation-text">${questionData.explanation}</div>`;
            html += `<div class="source-text">来源: ${questionData.source}</div>`;
            
            resultBox.innerHTML = html;
            resultContainerEl.appendChild(resultBox);

            // 禁用所有选项的点击事件，并高亮正确/错误答案
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                // 高亮正确答案
                if (index === questionData.correctAnswerIndex) {
                    child.classList.add('correct'); // 需要添加CSS样式
                    child.style.backgroundColor = '#d4edda';
                    child.style.borderColor = '#c3e6cb';
                }
                // 如果选错了，高亮错误选项
                if (!isCorrect && index === userAnswers[currentQuestionIndex]) {
                    child.classList.add('incorrect'); // 需要添加CSS样式
                    child.style.backgroundColor = '#f8d7da';
                    child.style.borderColor = '#f5c6cb';
                }
            });
        }

        function goToNextQuestion() {
            if (currentQuestionIndex < quizData.length - 1) {
                currentQuestionIndex++;
                loadQuestion();
            } else {
                showFinalScore();
            }
        }

        function goToPreviousQuestion() {
            if (currentQuestionIndex > 0) {
                currentQuestionIndex--;
                loadQuestion();
            }
        }
        
        function showHint() {
            const currentQuestion = quizData[currentQuestionIndex];
            if (currentQuestion.hint) {
                hintContainerEl.textContent = currentQuestion.hint;
                hintContainerEl.style.display = 'block';
            } else {
                hintContainerEl.style.display = 'none';
            }
        }

        function showFinalScore() {
            document.querySelector('.quiz-body').style.display = 'none';
            document.getElementById('quiz-footer').style.display = 'none';

            const correctCount = score;
            const totalQuestions = quizData.length;
            const answeredCount = userAnswers.filter(a => a !== null).length;
            const wrongCount = answeredCount - correctCount;
            const skippedCount = totalQuestions - answeredCount;
            const accuracy = totalQuestions > 0 ? Math.round((correctCount / totalQuestions) * 100) : 0;
            const errorRate = totalQuestions > 0 ? Math.round((wrongCount / totalQuestions) * 100) : 0;

            const finalScoreHtml =
                '<div class="final-score-container">' +
                '<h2>答题报告</h2>' +
                '<div class="score-summary">' +
                '<div class="score-card">' +
                '<h3>得分</h3>' +
                '<p>' + correctCount + ' / ' + totalQuestions + '</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>正确率</h3>' +
                '<p>' + accuracy + '%</p>' +
                '</div>' +
                '<div class="score-card">' +
                '<h3>错误率</h3>' +
                '<p>' + errorRate + '%</p>' +
                '</div>' +
                '<div class="score-card score-details">' +
                '<table>' +
                '<tr><td>正确</td><td>' + correctCount + '</td></tr>' +
                '<tr><td>错误</td><td>' + wrongCount + '</td></tr>' +
                '<tr><td>未答</td><td>' + skippedCount + '</td></tr>' +
                '</table>' +
                '</div>' +
                '</div>' +
                '<div class="report-actions">' +
                '<button id="review-btn">回顾测验</button>' +
                '<button class="primary" onclick="location.reload()">再试一次</button>' +
                '</div>' +
                '</div>';

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            if (reportEl) {
                reportEl.remove();
            }
            quizContentEl.insertAdjacentHTML('beforeend', finalScoreHtml);
            document.getElementById('review-btn').addEventListener('click', reviewQuiz);
        }

        function reviewQuiz() {
            const reportEl = document.querySelector('.final-score-container');
            if (reportEl) {
                reportEl.remove();
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            document.querySelector('.quiz-body').style.display = 'block';
            document.getElementById('quiz-footer').style.display = 'flex';
            
            currentQuestionIndex = 0;
            loadQuestion();
            updateNavigationButtons(); // Ensure nav buttons are correctly displayed
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        // Event Delegation for options
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            if (event.target && event.target.matches('li.option-item')) {
                // Check if the question has already been answered
                if (userAnswers[currentQuestionIndex] === null) {
                    const selectedIndex = parseInt(event.target.dataset.index, 10);
                    selectOption(selectedIndex);
                }
            }
        });

        prevBtn.addEventListener('click', goToPreviousQuestion);
        nextBtn.addEventListener('click', goToNextQuestion);
        hintBtn.addEventListener('click', showHint);
        
        // 初始加载
        loadQuestion();
      </script>
    </body>
    </html>
  